Experimental and epidemiologic evidence suggests human ovarian cancer is caused by hypergonadotropic hypogonadism (high gonadotropins consequent to failing ovaries). To identify risk factors linked to ovarian cancer thru this model, a population based case-control study is proposed using 650 ovarian cancer cases newly diagnosed in three Northeast Massachusetts counties and the state of New Hampshire and using age and residence matched controls selected via random digit dialing. Data will be obtained thru personal interview, a self-administered dietary questionnaire, and blood collection. Key variables possibly linked to hypogonadism and ovarian cancer are high galactose consumption and deficient galactose metabolism. The use of galactose rich foods will be assessed and analyzed in perspective of the subject's ability to metabolize galactose. Biochemical activity of three key enzymes will be determined (galactokinase, galactose- 1-phosphate uridyl transferase, and uridine diphosphogalactose-4- epimerase). Other exposures possibly linked to hypogonadism to be assessed include smoking, caffeine, and tannic acid consumption. Reproductive variables, oral contraceptive (OC) use, and talc exposure will also be assessed to determine their interrelationship with the environmental and biochemical risk factors, particularly, whether the effect of oocyte toxins on ovarian cancer risk is more apparent among women who have never used OC's. As a secondary aim we will create a serum and buffy coat bank to permit a search for DNA markers possibly related to ovarian cancer including genetic alterations related to the locus for galactose transferase or to p53 which we speculate may indirectly relate to galactose metabolism, or via an alternate cause of hypogonadism involving chromosome deletions in the region Xq21-27. Knowledge of genetic, biochemical, and environmental factors associated with ovarian cancer thru hypergonadotropic hypogonadism has public health importance in devising strategies for prevention of this disease. The role of galactose rich foods in ovarian cancer etiology is particularly important because of a substantial increase in the use of these foods in the United States.